1. Field of the Invention
This invention relates in general to apparatus for mounting a computer terminal or word processor or similar office equipment on a base such that it can be vertically and angularly adjusted relative to the base.
One is at pains given work at a terminal such as represented, for example, by a video terminal or the like, to erect the terminal in a position in which the fewest possible disturbing influences are exerted on the operator with respect, for example, to viewing direction, distance and reflection of extraneous light.
2. Description of the Prior Art
It is known from the DE-OS No. 28 47 135 to erect a video terminal on a supporting apparatus. This consists of a base part with a turntable ring seated thereon, a supporting arm at a horizontally proceeding shaft being applied to said ring for height adjustment. A pivotable supporting arm for carrying the video terminal is supported at the free end thereof, said pivotable supporting arm always guaranteeing a parallel attitude of the video terminal relative to itself given a height adjustment on the basis of a parallel guide disposed in the supporting arm. The supporting apparatus also comprises a weight equalization means by means of which the torque exerted on the supporting arm with respect to its first axis by the weight of the video terminal and of the supporting arm is at least approximately compensated in every position of the supporting arm. The weight equalization means is formed by a torsion spring which is disposed in the articulated joint between the supporting arm and the turntable ring and which coaxially surrounds the first axis.
The design of the weight equalization means as a torsion spring which is disposed in the articulated joint has the disadvantage, however, that installation connected with a pre-stress of the torsion spring is difficult to manipulate with an increasing spring power of the torsion spring. Torsion springs having low spring power, however, exclude the utilization of the supporting apparatus for large video terminals. The height adjustment with the supporting arm has the disadvantage that the location of the center of gravity changes given a higher adjustment, so that a relatively large or, respectively, heavy base part must be employed. Since the torsion spring does not have a linear force function, the height adjustment dependent on the height must ensue with differing force. The overall structure is thereby relatively complicated and intractable.
Further known from the E-PS No. 00 41 804 is an apparatus for the releasable seating of a terminal which contains a carrier plate shaped calotte-like which accepts the terminal and which is rotatably and pivotably disposed on a supporting element and comprises a horizontal swing slot for the acceptance of a retaining element allocated to the supporting element. A screwed connection thereby serves as retaining element.